Setting back a 6.5-284 barrel, rechamber to 264 WM?

I picked up a 31" Palma contour Krieger barrel in 6.5-284 that had about 750 rds through it according to the owner who shoots F class (I think) and rebarrels every year. It is currently threaded for a Stolle action but has a nice long shank on it and is of standard diameter 1.25" or so. I bought it with the thought of having the threads cut off and having it threaded for a Rem 700 and chambered to 264 Win mag. It is 1 in 8" twist and was well cared for.

My question is, what percentage of barrel life could I reasonably expect compared to a new barrel when I would be essentially reaming out a whole new chamber and throat area about 1.5-2" deeper?

Sam

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I believe that I remember one of the reputable smiths on this site claiming you will get about half of the life after setting back. If it will last 1000 on the first chamber, you should get a 500 on the setback. Just some food for thought. I have not had to set my f class rifle back...yet.